Probing the relationship between late endogenous ERP components with fluid intelligence in healthy older adults

The world population is rapidly aging, bringing together the necessity to better understand the advancing age. This characterization may be used to aid early diagnosis and to guide individually-tailored interventions. While some event-related potential (ERP) components, such as the P300 and late positive complex (LPC), have been associated with fluid intelligence (Gf) in young population; little is known whether these associations hold for older people. Therefore, the main goal of this study was to assess whether these ERP components are associated with Gf in the elderly. Fifty-seven older adults performed a continuous performance task (CPT) and a visual oddball paradigm while EEG was recorded. Participants were divided into two groups, according to their performance in the Raven's Advanced Progressive Matrices test: high-performance (HP) and low-performance (LP). Results showed that the HP group, compared to the LP group, had higher LPC amplitudes in the CPT and shorter P300 latencies in the oddball task, highlighting the role of ERP components as a potential electrophysiological proxy of Gf abilities in the elderly.We thank Camara Municipal de Vila Nova de Famalicao (Dr. Rui Baptista and Bruno Gomes), Associacao Geracoes (Dr. Cristiana Oliveira, Clara and Daniela Silva), Santa Casa da Misericordia de Barcelos (Dr. Ricardo Vieira and Dr. Helder Longras), and Fundacao Bomfim (Dr. Raquel Polonia) for hosting the study; all the volunteers for their participation, as well as, Silvia Alves, Carla Barros, Anabela Fernandes and our colleagues from the Psychological Neuroscience Laboratory for all the help during data collection and recruitment. This work was supported by the Portuguese Foundation for Science and Technology (FCT) [Doctoral Grants No. SFRH/BD/80965/2011 (awarded to ACT) and No. PD/BD/105964/2014 (awarded to DRP)] and by the Bial Foundation (Grant Number #286/16). It was conducted at the Psychology Research Centre (PSI/01662), School of Psychology, University of Minho, and supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education (Grant Number UID/PSI/01662/2019), through the national funds (PIDDAC). DP was supported by FCT (Grant Number SFRH/BPD/120111/2016). SC was funded by the FCT (Grant Number IF/00091/2015) and COMPETE 2020 (Grant Number PTDC/PSI-ESP/29701/2017)

ERP evidence suggests executive dysfunction in ecstasy polydrug users

Background: Deficits in executive functions such as access to semantic/long-term memory have been shown in ecstasy users in previous research. Equally, there have been many reports of equivocal findings in this area. The current study sought to further investigate behavioural and electro-physiological measures of this executive function in ecstasy users. Method: Twenty ecstasy–polydrug users, 20 non-ecstasy–polydrug users and 20 drug-naïve controls were recruited. Participants completed background questionnaires about their drug use, sleep quality, fluid intelligence and mood state. Each individual also completed a semantic retrieval task whilst 64 channel Electroencephalography (EEG) measures were recorded. Results: Analysis of Variance (ANOVA) revealed no between-group differences in behavioural performance on the task. Mixed ANOVA on event-related potential (ERP) components P2, N2 and P3 revealed significant between-group differences in the N2 component. Subsequent exploratory univariate ANOVAs on the N2 component revealed marginally significant between-group differences, generally showing greater negativity at occipito-parietal electrodes in ecstasy users compared to drug-naïve controls. Despite absence of behavioural differences, differences in N2 magnitude are evidence of abnormal executive functioning in ecstasy–polydrug users

Neurophysiological Investigation of the Functional Interactions between Manual Action Control and Working Memory

Gündüz Can R. Neurophysiological Investigation of the Functional Interactions between Manual Action Control and Working Memory. Bielefeld: Universität Bielefeld; 2020

Fostering advances to neuropsychological assessment based on the Research Domain Criteria: The bridge between cognitive functioning and physiology

Objectives: The current review aimed to explore the advances in neuropsychological assessment in light of a recent research framework designed to improve our knowledge on mental health – the Research Domain Criteria (RDoC). Methods: RDoC proposals on neuropsychological tests were reviewed across the RDoC cognitive systems domain. The focus is on the physiological unit of analysis and the potential applications are illustrated given the functional relevance of RDoC constructs to psychopathological and neurological conditions. Results: The advances in neuropsychology anchored in RDoC are not observable in terms of innovative paradigms, but rather in the neurobiological correlates that may be obtained from the classical neuropsychological tasks. The behavior unit of analysis may be integrated with physiological outcomes while mapping distinct cognitive constructs simultaneously. Conclusions: Under the aegis of RDoC, the integration of multiple levels of analysis allows to obtain a more detailed and complete neuropsychological characterization with high potential to be translated into better intervention strategies.info:eu-repo/semantics/publishedVersio

Training of Working Memory Impacts Neural Processing of Vocal Pitch Regulation

Working memory training can improve the performance of tasks that were not trained. Whether auditory-motor integration for voice control can benefit from working memory training, however, remains unclear. The present event-related potential (ERP) study examined the impact of working memory training on the auditory-motor processing of vocal pitch. Trained participants underwent adaptive working memory training using a digit span backwards paradigm, while control participants did not receive any training. Before and after training, both trained and control participants were exposed to frequency-altered auditory feedback while producing vocalizations. After training, trained participants exhibited significantly decreased N1 amplitudes and increased P2 amplitudes in response to pitch errors in voice auditory feedback. In addition, there was a significant positive correlation between the degree of improvement in working memory capacity and the post-pre difference in P2 amplitudes. Training-related changes in the vocal compensation, however, were not observed. There was no systematic change in either vocal or cortical responses for control participants. These findings provide evidence that working memory training impacts the cortical processing of feedback errors in vocal pitch regulation. This enhanced cortical processing may be the result of increased neural efficiency in the detection of pitch errors between the intended and actual feedback

Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

OBJECTIVE: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenance and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task. METHODS: 41 depressed participants and 41 age and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). RESULTS: MDD participants had prolonged response times and more positive frontal P3 amplitudes (i.e., Fz) relative to controls, mainly in the most difficult 2-back condition. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty. CONCLUSIONS: Depression is associated with generalized psychomotor slowing of working memory processes, and may involve compensatory hyperactivity in frontal and parietal regions. SIGNIFICANCE: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable working memory performance to controls

Post-training load-related changes of auditory working memory: An EEG study

Working memory (WM) refers to the temporary retention and manipulation of information, and its capacity is highly susceptible to training. Yet, the neural mechanisms that allow for increased performance under demanding conditions are not fully understood. We expected that post-training efficiency in WM performance modulates neural processing during high load tasks. We tested this hypothesis, using electroencephalography (EEG) (N = 39), by comparing source space spectral power of healthy adults performing low and high load auditory WM tasks. Prior to the assessment, participants either underwent a modality-specific auditory WM training, or a modality-irrelevant tactile WM training, or were not trained (active control). After a modality-specific training participants showed higher behavioral performance, compared to the control. EEG data analysis revealed general effects of WM load, across all training groups, in the theta-, alpha-, and beta-frequency bands. With increased load theta-band power increased over frontal, and decreased over parietal areas. Centro-parietal alpha-band power and central beta-band power decreased with load. Interestingly, in the high load condition a tendency toward reduced beta-band power in the right medial temporal lobe was observed in the modality-specific WM training group compared to the modality-irrelevant and active control groups. Our finding that WM processing during the high load condition changed after modality-specific WM training, showing reduced beta-band activity in voice-selective regions, possibly indicates a more efficient maintenance of task-relevant stimuli. The general load effects suggest that WM performance at high load demands involves complementary mechanisms, combining a strengthening of task-relevant and a suppression of task-irrelevant processing

Behavioural and electrophysiological modulations induced by transcranial direct current stimulation in healthy elderly and Alzheimer’s disease patients: A pilot study

Available online 26 August 2019Objective To investigate whether anodal and cathodal transcranial direct current stimulation (tDCS) can modify cognitive performance and neural activity in healthy elderly and Alzheimer’s disease (AD) patients. Methods Fourteen healthy elderly and twelve AD patients performed a working memory task during an electroencephalogram recording before and after receiving anodal, cathodal, and sham tDCS over the left dorsolateral prefrontal cortex. Behavioural performance, event-related potentials (P200, P300) and evoked cortical oscillations were studied as correlates of working memory. Results Anodal tDCS increased P200 and P300 amplitudes in healthy elderly. Cathodal tDCS increased P200 amplitude and frontal theta activity between 150 and 300 ms in AD patients. Improved working memory after anodal tDCS correlated with increased P300 in healthy elderly. In AD patients, slight tendencies between enhanced working memory and increased P200 after cathodal tDCS were observed. Conclusions Functional neural modulations were promoted by anodal tDCS in healthy elderly and by cathodal tDCS in AD patients. Significance Interaction between tDCS polarity and the neural state (e.g., hyper-excitability exhibited by AD patients) suggests that appropriate tDCS parameters (in terms of tDCS polarity) to induce behavioural improvements should be chosen based on the participant’s characteristics. Future studies using higher sample sizes should confirm and extend the present findings.This study was funded by the Italian Ministry of Health GR-2011-02349998 to MCP and the European Commission Marie-Skłodowska Curie Actions, Individual Fellowships; 655423-NIBSAD to JC

Altered event-related potentials and theta oscillations index auditory working memory deficits in healthy aging

Speech comprehension deficits constitute a major issue for an increasingly aged population, as they may lead older individuals to social isolation. Since conversation requires constant monitoring, updating and selecting information, auditory working memory decline, rather than impoverished hearing acuity, has been suggested a core factor. However, in stark contrast to the visual domain, the neurophysiological mechanisms underlying auditory working memory deficits in healthy aging remain poorly understood, especially those related to on-the-fly information processing under increasing load. Therefore, we investigated the behavioral costs and electrophysiological differences associated with healthy aging and working memory load during continuous auditory processing. We recorded EEG activity from 27 younger (∼25 years) and 29 older (∼70 years) participants during their performance on an auditory version of the n-back task with speech syllables and 2 workload levels (1-back; 2-back). Behavioral measures were analyzed as indices of function; event-related potentials as proxies for sensory and cognitive processes; and theta oscillatory power as a reflection of memory and central executive function. Our results show age-related differences in auditory information processing within a latency range that is consistent with a series of impaired functions, from sensory gating to cognitive resource allocation during constant information updating, especially under high load